Rendering problem.

Okay so I have a major rendering problem which turns out to be very strange in my opinion.

Okay so I am doing a video with three different angles which are all in sync from different devices. I have never done 3 before, I've only done 2.
When I go to render my project it doesn't include one of my angles. It renders the new angle but not the angle that has actually worked before.

However the slowed down versions on the angle do render....

Check the pictures please.

As you can see in the interface picture I have also tried adding the angle to the render video but that doesn't work either.

Have you tried a separate Edit with three clips: i.e. taken some weeks ago?
These could stand-in for the three cameras.
( If you want to "tag" them you could adjust the Track-wide colour balance: Camera one Red, Camera Two yellow, Camera Three Green. (ie following Traffic-lights).
However, you could try taking three Titles, which can be numbered 1,2,3 and then you don't need to use colours.

How are you switching between the cameras? I can't see it clearly, but it looks like a conventional Edit where the uppermost track is masking anything beneath it.
Have you tried Composite-level switching?

I don't see how this can be anything to do with render settings. Vegas always shows the top or upper track. Unless you do something to cause it not to. What have you done on track one ? Is there some sort of compositing mode applied that is masking a track ? I can't see from the picture you posted.

Is this correct :
Track 1 is blank
Track 2 is the lower left PiP
Track 3 is the Big background image
Track 4 is audio

If this is the case, I need a bigger picture of your time line to see what you have do to get three camera angles using only two tracks. One important note is that you must have the correct project properties when changing the size of a clip/event or you will have difficulty later during the render.

"It renders the new angle but not the angle that has actually worked before. "

What does that mean?
Just about the only thing that is clear from your photo is that you have applied track motion to move the image on track 2. Is this what you're trying to do, use a "Picture In Picture" for the different angles?
You only have two tracks of video, so where's the third angle? Or is track 3 (as it appears to be from the photo) a previous render which already has a PiP?

As has been said - what you have shown us is that you are only rendering 2 Tracks and that equates to ONLY 2 angles. Where IS that missing 3rd angle/track? ( Clue...)

What I don't understand, and fail to see is that you are obviously capable of rendering 3 angles from 3 sources, but you aren't demonstrating that this IS what you are doing. Why? So I can only conclude: you are either missing the information or have posted the wrong screenshots - and until you demonstrate what is going on, you've left us in the dark. You can't have it both ways. Put simply, you aren't showing us what is going on. Do check and recheck your information.

Agreed that a PC needs to be 2-core or Quad ++ but I believe this only affect the duration of Rendering. Whereas a powerful PC might take 30mins, a lesser PC ( er, like mine ) may estimate a couple of Hours. Indeed sometimes overnight I put the PC into Render. Just make sure the Turn-off options are set ( 1-hour say ), longer than the Render Time. It's only an "estimate".

I'm getting the impression OP hasn't set up his Editor correctly, as suggestion in Post #6.